Modelo analítico para determinação do comprimento da rótula plástica de pilares de concreto armado sob flexão lateral via simulação computacional e análise experimental

Abstract

An analytical method for calculating the lateral displacements of reinforced concrete columns is proposed based on the plastic hinge length. An equation for calculating the plastic hinge length was also introduced based on the variables axial load ratio (P/Po), shear-span ratio (l/h), and longitudinal reinforcement ratio (ρs). The finite element program ABAQUS/CAE was used to analyze the variables and the propagation of plastic hinge length. Forward, the method was validated by an experimental database from the literature and by columns tested experimentally in the laboratory, including 6 full-scale columns. The computational analysis concluded that increasing the variables progressively increased the plastic hinge length. Experimentally, for P/Po=0.2 and P/Po=0.4, an increase of 1.2 times in the plastic hinge length was observed from 0.2 to 0.4, an increase from 1.0 to 2.0 was observed in the plastic hinge length when slenderness range from l/h=10 to l/h=12, respectively, and an increase from 0.2 to 2.0 in the plastic hinge length was observed when longitudinal reinforcement ratios range from 2.0% to 3.0%, respectively. After this analysis, an analytical model for calculating the lateral displacements of columns was introduced, and an equation for calculating the plastic hinge length was proposed. The proposal was validated by an experimental database with 61 elements obtained from the literature and compared with methods available in the literature. Other analytical models, also based on the formation of plastic hinge length, were compared to the proposal. The results indicated that both the adopted method and the proposed equation are suitable for estimating displacements, with greater accuracy in displacement estimates compared to other available methods.